Checksums must also work for uneven number of bytes.

This commit is contained in:
Guus Sliepen 2003-03-29 22:11:22 +00:00
parent c3ad3731a8
commit 8285827da1

View file

@ -17,7 +17,7 @@
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
$Id: route.c,v 1.1.2.48 2003/03/29 21:58:35 guus Exp $
$Id: route.c,v 1.1.2.49 2003/03/29 22:11:22 guus Exp $
*/
#include "config.h"
@ -76,10 +76,13 @@ uint16_t inet_checksum(void *data, int len, uint16_t prevsum)
uint16_t *p = data;
uint32_t checksum = prevsum ^ 0xFFFF;
len /= 2;
while(len--)
while(len >= 2) {
checksum += *p++;
len -= 2;
}
if(len)
checksum += *(unsigned char *)p;
while(checksum >> 16)
checksum = (checksum & 0xFFFF) + (checksum >> 16);